Control of position indicator for elevators



Sept. 8, 1959 .1. Lus-ri ET AL 2,903,093

CONTROL OF POSITION INDICATOR FOR ELEVATORS Filed Oct. 1, 1958 JOHNLUST! ZOBERT WAYNE MADISON 'NVENTO RS BY j W ATTORNEY United StatesPatent CONTROL OF POSITION INDICATOR FOR ELEVATORS John Lusti, RiverVale, NJ., and Robert Wayne Madison, Staten Island, N.Y.,. assignors toOtis Elevator Company, New York, N.Y., a corporation of New JerseyApplication October 1, 1958, Serial No. 764,671

6 Claims. (Cl. 187-29) The invention relates to position indicatingmechanism for elevators and especially to control mechanism therefor.

, In elevator installations it is usual to provide a device to indicatewhich elevator cars are in service and the position of the various carsin their respective hoistways. Also, it is usual to indicate thisinformation visually on one or more strategically placed panels by meansof sequentially actuated electric light sources positioned in a row foreach car, each light source in the row corresponding to a floor servedby the car. Such a panel is usually located at the main lobby, where itis accessible to the starter, who supervises the operation of theelevators. A duplicate panel is occasionally located in the maintenancecenter of the building, where it is accessible to maintenance personnel.

It is desirable that this device remains operative in the event that anelevator car stops operating due to an abnormal stopping of its hoistingmechanism, such as a power failure caused by an overload, so that thestarter and maintenance personnel may locate the position of the carthus stranded in the hoistway. This is especially true in modern dayelevator installations, where elevators without attendants operate as agroup according to predetermined operating programs.

In such installations automatic mechanism is provided to change theelevator operation from one program to another as the elevator traflicvaries throughout the day and in so doing, one or more elevators mayrepeatedly be taken out of service and later put back in service inaccordance with the operation desired. When an elevator is thus takenout of service and parked at a floor by the automatic mechanism, theposition indicator light sources are extinguished to denote itsnon-operating condition. However, the supervisory personnel cannoteasily determine whether the car had been properly taken out of serviceby the automatic mechanism, since should an abnormal elevator stoppingoccur, the position indicator light sources would also be extinguished.Furthermore, in such a case they cannot readily determine where in thehoistway the stranded car is located.

It is therefore an object of this invention to provide a device whichwill maintain the electric car position indicator device operative whenthe elevator hoisting mechanism is stopped abnormally.

It is another object of this invention to provide a device which willextinguish the indicating light sources of an electric visual carposition indicator when a car is removed. from service in a normalmanner, but which will maintain that light source lit to indicate theposition of the car when the car becomes non-operative due to a powerfailure of its hoisting mechanism.

Features and advantages of the invention will be apparent from the aboveand from the following description of operation when considered inconjunction with the drawings in which:

Figure 1 is a simplified schematic wiring diagram of a portion of theelevator hoisting mechanism power and 2,903,093 Patented Sept. 8, 1959control circuits and of the position indicating device circuitsembodying the invention;

Figure 2 is a side elevation of a form of toggle switch used in theposition indicating device circuits of Figure 1, with portions brokenaway to show certain details of the interior thereof; and

Figure 3 is a cross-sectional view of the same toggle switch takenapproximately along the line 33 of Figure 2.

Referring to Figure 1, the elevator car hoisting mechanism is shown asconsisting of a direct current hoisting motor having an armature MAwhich is supplied with current at a variable voltage from a generatorarmature GA which is rotated by a driving motor having a rotor DMR. .Thepolyphase field winding DMF of the driving motor is delta connected andis supplied with three phase alternating power from any suitable source(not shown) over supply lines I, II and III. Coils designated 0A and OBof corresponding overload relays are connected in supply lines I andIII, respectively. These relays are preadjusted to operate when thecurrents passing through their respective coils exceed a predeterminedvalue for a predetermined time, deemed an overload.

An exciter driven by the driving motor and consisting of an armatureEAM, a self-excited field winding EF and a series field winding ESFsupplies current to the sepa jrately excited generator field winding GF,hoistway machine field winding MP, the coil CA of the electro magneticpotential switch and brake release coil BR. The generator has a seriesfield winding GSF.

Supply lines W10+ and W11 apply unidirectional power to coil K of thedriving motor stopping switch and to the set of and reset coils PF ofthe position indicator control switch. A circuit breaker or fusedesignated F is connected in supply line W10+.

For simplicity, the activating coils of the following electromagneticswitches have not been shown, they being operated in the usual fashionand only their contacts, as shown in the circuit of Figure 1, beinginvolved in the operation of the subject invention. These switches andtheir actuating mechanisms are described in detail in Patent No.2,761,528 to W. F. Glaser et al. issued September 4, 1956 in whichsystem the subject invention may be utilized:

DNDown direction switch HField and brake switch MGSMot0r generatorstopping switch UPUp direction switch Up direction switch (UP) and downdirection switch (DN) are moved to and latched in their operatedconditions incident to the car becoming preset for travel in the up andthe down directions, respectively. Conversely, these switches are movedto their unoperated conditions when the car is preset for travel in theopposite directions. Field and brake switch (H) is energized incident tothe car being moved away from a floor landing and is deenergized whenthe car stops at a floor landing. Motor generator stopping switch (M68)is responsive to automatic and manual controls which are actuatedincident to changing the mode of operation of the elevator system asrequired.

Electromagnetic relay and switch contacts are designated by letterscorresponding to their activating coils, number sufiixes being added todistinguished between sets of contacts on the same coil or switch andare shown for the unergized condition of their coils. Position indicatorcontrol switch (PF) is shown in its reset condition.

Alternating power from any suitable source (not shown) is supplied overlines W12 and W13 to the position indicator lamp circuit of Figure 1,wherein the position indicator lamps are designated PI-l through PI-S,

the number sufiixes of each lamp corresponding to the floor landing forwhich that lamp is provided. This posi= tion indicator lamp circuit isthe subject matter of the copending application of A., E. Prince, No.768,368, filed October 20', 1958. Position indicator lamps PI-l-S maybemounted in a starters panel similar to the one disclosed inFigure l7of.Patent No. 2,589,242. to Glaser etall, issued March 18, 1952'. Singlepole, double throw toggle switches TS1-4 having stationary contacts 13,14 and movable contacts 24, 25 are. of the snap action latching type andare sequentially actuated in accordance with movement of the elevatorcar. These switches may be mounted in the hoistway at each floor landingto be actuated by a cam C carried by the car or may be mounted on thefloor barsof a selector, such as disclosed in Figure 2 of theaforementioned Glaser Patent No. 2,589,242, to be actuated by a canrC'carried by the crosshead of the selector.

The construction of toggle switches TS1-4 is more fully shownin Figures2 and 3. The various parts are shown mounted. on a switch housingconsisting of two insulatingrnembers 4-and 5 which in turn are mountedon a. selector floor bar 6 by means-of three. studs 7. These studspassthrough apertures in floor bar 6' (but donottouchit) and housing members4 and 5 and are secured in place by nuts.8 and lock washers 9. Thethreaded end portion of studs 7 are made. long enough to serveas.terminals for connecting the various electrical leads illustrated in theposition indicator lamp. circuit of Figure l. The heads 11 of two of.the studs 7 have formed thereon stationary contacts 13 and 14,respectively,.of silver material. Defined in the head 16 of the thirdstud 7. is a groove 17 which forms. a pivotfor metallic. switch lever21, having a substantially cross shape with one end of its verticallyextending. member 21a pivotally positioned in groove 17. Itshorizontally extending member has affixed at one end a contact 24 whichengages with stationary contact 13 when switch lever. 21 isin oneextreme position, and at its other end a contact 25 which engages withstationary contact 14 when. switch lever 21 is in the other extremeposition. A substantially U-shaped toggle link 27 having a web portion27a is pivotally secured to housing member. 5 by means of two pins 28.Shoulders 29 and 30.formed-in housing member 5 act as stops to limit themovement of toggle link- 27. A roller 32 of insulating materialisrotatably secured to toggle link 27 by means-of stud 34 the end ofwhich protrudes through web portion 27a. A coil spring 36 undercompression has one' end positioned around the protruding end of stud 34and presses at that end'against web portion27a and at the other endagainst oversize washer 38 which in turn rests on shoulders formed onthe adjacent end of vertically extending member 21a of switch lever 21.

In the manner characteristic of such switches, the movement of togglelink 27 to a position slightly past its-midposition results in a snapaction of switch lever 21. to open the contacts at one of its ends andclose those: at its opposite end substantially instantaneously. Spring36 provides, in either position, sufficient tensionto hold: thecontacting members securely together.

The operation of the arrangement can be visualized with. reference toFigure 1, if it is assumed. that. the motor. generator set is notrunning and the car is parked at the first floor landing. Further assumethat its up direction switch (UP) (not shown) is latched in itsoperated; condition with its contacts. UPI and UP2 engaged topreset thecar for upward travel. In such av case motor generator stopping switch(MGS) (-not shown) is inits energized condition-maintainingitscontactsMGSl separated, and the set coil PF of the position indicatorcontrol: switch is energized through driving motor stopping switchcontacts K1. With the position indicator control switch (PF) in itsset.condition, contacts PF2 are closed and contacts PEI are 4' separated tomaintain position indicator lamps PI-l-S extinguished.

Next assume that motor generator stopping switch (MGS) (not shown) isdeenergized to start the motor generator set running and that it closesits contacts MGSll to complete a circuit for the coil K of the drivingmotor stopping switch. Contacts K3, K4 and K5 engage to complete.thecircuitsfor. polyphase'; field winding DMF to start the drivingmotor.Rotation of the motor causes the. exciter. voltage to buildupto fullvalue and energize. separately excited hoisting motor field' MF and thecoil CA of the potential switch. Potential switch contacts CA1 and CA2engage without effect at this time. i

The driving motor stopping switch also Separates its contacts Kldeenergizing the set coil PF of the position indicator control switchand engages its contacts K2 energizing the reset coilPF of the positionindicator control switch, the latter circuit extendingthrough W10'+, F,0A1, 0B1, K2, the reset coil PF, PF2 and W11'. The position indicatorcontrol switch moves to its reset position separating contacts PFZ andengaging .contacts PFl to complete a circuit for position indicator lampPI-l, the circuit extending through W12, PFl, toggle switches.TS4-TS1,PI1 and W13.

Incident to the car leaving. the door, field and brake switch (H) (not.shown) is actuatedengaging contacts H1 and H2. to complete. the circuit.for brake release coil- BR, contacts- H3 and H4 to complete the. circuitthrough contacts. UPI and UP2 for. the generator field windingv GF andseparating contacts HS. to. disconnect generator field. windingGF fromacross. generator. armature GA. The completionof the. circuitforthegenerator separately excited field windingGF causes current to besupplied from generator armature GA to hoisting motor armature MA.causingthe elevator hoisting motor to start. the. car inthe updirection.

Asthe car moves upward, toggle switch T81 is actuated in accordance withcar movement. by camC' separating contacts 25 and 14-of toggle switchTS1 to extinguish position indicator lamp PI-1 and engage immediatelycontacts 24 and 13 of switch TS]; to light lamp P1 2 to indicate the.position. of the car atthe: second floor landing.

As the. car continues moving upward, toggle switches TSZ. to TS4 are.actuated in sequence to indicate the position. of. the. car atthe.third,. fourth and fifth floor landings,,r.espectively. The actuation ofswitch lever. 21 (Figure 3.) of each toggle switch.TS1.-4 is so rapidthat a substantially. continuous indication of. the. position. oftheicar is obtained.

As the. car arrives at. the upper floor landing, field and brake switch.(H) (not shown) is. deenergized,.separatingcontactsI-Il. and H2 todeenergize brake release coil BR andapply the brake, contacts H3 andH4,to disconnect the generator. separately. excited. field winding GFfrom the exciter to bringthecar to a stop at the upper floor landing.and engaging contacts H5. reconnecting generator. field winding.- GFacross generator. armature GAlsubstantially to destroy theresidualfluxofthe generator field.

Incident to the car stoppingat, the upper floorlanding, up directionswitch (UP) (not shown) is. deenergized separating its contacts UP.1 andUP2,.and.down.direc.- tion switch (DN) (-not shown) is energized.andlatched into. operatedcondition. engaging contacts DN1 and DN2presetting the car for travelinthe.downdirection.

Preparatory to startingdown switch (H) is energized, engaging contactsH1 and H2..to.eornplete.a circuit. for brake release coil BR. Switch (H)also. engages contacts H3 and.H4. and separates contacts H5 energizingthe generator. field GF through contactsDNl and DN2 to supply current tohoisting motor armature MA to move the car in thedown-direction.. As thecar moves downward, cam C actuates switch TS4 separatingits contacts 24and 13 to extinguish lamp PI-S and engaging its contacts 25 and 14 tolight lamp PI-4, the latter circuit extending through W12, PFl, contacts25 and 14 of switch TS4, contacts 24 and 13 of switch TS3, PI-4 and W13.As the car proceeds downward, toggle switches TS1--TS3 are actuated inreverse sequence to indicate continuously the position of the car.

As the car arrives at the first floor landing, it is brought to a stopin a manner similar to that described in regard tostopping at the upperfloor landing, down direction switch (DN) being deenergized and updirection switch (UP) being energized and latched into operatedcondition to preset the car for travel in the up direction.

Now assume that because of light trafiic conditions in the building thecar is to be taken out of service and its motor generator set stopped inthe normal manner either through manual controls or in response to theaforementioned automatic program controls. To accomplish this motorgenerator set stopping switch (MGS) (not shown) is energized in responseto the manual or automatic controls, thereby separating its contactsMGSl breaking the circuit for the coil of driving motor stopping switch(K) which releases. Switch (K) separates contacts K3, K4 and K5interrupting the power supplied'to polyphase field winding DMF of thedriving motor which stops running.

Switch (K) also separates contacts K2 in the circuit of reset coil PF ofthe position indicator control switch and engages contacts K1 in thecircuit of set coil PF of that switch which is thus actuated to its setposition. The position indicator control switch engages contacts PF2 inits reset coil circuit without effect at this time, since contacts K2are already opened. This switch also separates its contacts PF 1extinguishing position indicator lamp PI1 to signify that the car hasbeen taken out of operation and its motor generator set has beenstopped.

Next assume that while the car is traveling upward and approximately atthe third floor landing (at which position position indicator lamp PI3is lit) the motor generator set is stopped abnormally due to a powerfailure of the motor control circuits (circuit breaker or fuse F isoperated or excessive load on the driving motor causes overload relaysOA and/or OB to be actuated). In such a case the power supply to coil Kof the driving motor stopping switch and the set and reset coils PF ofthe position indicator control switch is interrupted. The driving motorstopping switch (K) releases separating its contacts K3, K4 and K5 tointerrupt the power supply to field winding DMF of the driving motorbringing that motor to a stop. As the driving motor comes to a stop, theexciter voltage decreases deenergizing coil CA of the potential switchwhich separates its contacts CA1 and CA2 interrupting the currentflowing to brake re lease coil BR and generator field winding GP toapply the brake and stop the car. Incident to the car stopping, fieldand brake switch (H) (not shown) deenergizes separating contacts H3 andH4 and engaging contacts H5 reconnecting generator field winding GFacross generator armature GA.

The driving motor stopping switch (K) also engages contacts K1 in theset coil PF circuit of the position indicator control switch withouteffect since either circuit breaker or fuse F, contacts 0A1 and/orcontacts 0B1 of the overload relays have been actuated, as has beenpreviously stated, and have interrupted the circuit of this coil.Therefore the position indicator control switch (PF) remains in itsreset position and its contacts PFI remain closed maintaining theposition indicator lamp PI-3 illuminated to indicate the position of thestranded car. The driving motor stopping switch (K) also separates itscontacts K2 without effect.

It will be noted that when the motor generator set is stopped normally,the position indicator lamp is extinguished indicating that the car hasbeen taken out of operation in a normal manner; but when the motorgenerator set is stopped due to an overload, the position indicator lampremains illuminated indicating to supervisory personnel that an abnormalmotor generator set stopping has occurred and indicating the position ofthe stranded car in the hoistway.

When the trouble is remedied and power is again supplied to the drivingmotor control and position indicator control circuits, the set coil PFof the position indicator control switch is energized through contactsK1 and op crates to its set condition separating contacts PFl, therebymomentarily extinguishing position indicator lamp PI3. This switch (PF)also closes contacts PF2. The driving motor stopping switch (K) is alsoagain energized and separates contacts K1 breaking the circuit to theset coil PF of the position indicator control switch and engagescontacts K2 completing a circuit through contacts PF2 for the reset coilPF of this switch. Switch (PF) operates to its reset position separatingcontacts PFZ and reclosing contacts PFl to illuminate again positionindicator lamp PI-3. Switch (K) also engages contacts K3, K4 and K5supplying power to driving motor field winding DMF to restart the motorgenerator set and in turn the hoisting machine, as has been previouslydescribed, thereby causing the car to continue its upward travel.

As changes can be made in the above described construction and manyapparently different embodiments of this invention can be made withoutdeparting from the scope thereof, it is intended that all mattercontained in the above description or shown on the accompanying drawingsbe interpreted as illustrative only and not in a limiting sense.

What is claimed is:

1. In an elevator installation in which an elevator car travels in ahoistway and serves several floor landings of a building and in whichthere are provided an elevator hoisting machine adapted for propellingsaid car in said hoistway, a motor generator set adapted for energizingsaid hoisting machine, means for controlling the opera tion of saidmotor generator set, including motor starting and stopping mechanism,overload mechanism operatively responsive to an overload of said motorgenerator set for actuating said motor stopping mechanism to stop saidmotor when an overload occurs, and car position indicating meansincluding a plurality of light sources, one each of which corresponds toa floor landing served by said car, said position indicating means beingadapted for indicating the position of said car in said hoistway byselectively energizing said light sources in accordance with movement ofsaid car in said hoistway, characterized in that control mechanismresponsive to actuation of said motor generator set control is providedfor maintaining said position indicating means operative when said motorstopping mechanism is actuated by said overload mechanism.

2. A car position indicator control adapted for use in an elevatorinstallation in which an elevator hoisting machine adapted forpropelling an elevator car in a hoistway, a motor generator set adaptedfor energizing said hoisting machine, and car position indicating meansincluding a plurality of position-indicating electric lamps adapted forindicating the position of said car in said hoistway are provided; saidposition indicator control comprising, normal motor generator setcontrol means adapted for starting and stopping said motor generator setand in turn said hoisting machine, emergency control means for stoppingsaid motor generator set when abnormal operation of said motor generatorset occurs, and electric switch means operatively responsive to saidnormal motor control means for extinguishing said position indicatinglamps only when said motor generator set is stopped by said normal motorcontrol means.

3. A car position indicator control adapted for use in an elevatorinstallation in which an elevator hoisting machine adapted forpropelling an elevator car in a hoistway, firstzcontrolzmeans adapted:for; controlling the tion'of'saidcarinsaid hoistway. are provided; saidposition indicaton control comprising, start and stop means forstarting. and stoppingsaid motor generator set, second control meansoperatively responsive-to-operation ofsaid first: control means, foractuating said. start and stopmeans, overload mechanism opera-tivelyresponsive to an overload' of said motor generator set, said overloadmechanism. actuating said start and stopmeans-toi stop said motorgenerator set when an overload occurs, and

electric switch-means operatively responsive tosaid secnd control meansand adapted for extinguishing said position indicating lamps only uponactuation of said start: and stopmeansito stop said= motor generator.set by. saidsecond control means.

4; A car. position'indicator control adaptedfor use in an elevatorinstallation in Which an elevator hoisting machine for propellinganelevator car in a. hoistway, a motor generator set for energizingsaid. hoisting-machine,, and car position indicating means including aplurality of electric position indicating lamps adapted for indicatingthe position. of said car in said hoistway are provided; said positionindicator controlcomprising, start and stop' meansfor starting andstopping said motor-generator set, control rneansoperable toactuatesaidi stop and start means, safety mechanism including overload devicesoperatively responsive to an overload of said motor generator set toactuate said start and: stop means to stop said motor generator set:when an overload occurs, and electric switch means selectivelyresponsive toactuation of said start and stop means to extinguish saidposition indicating. lamps only upon op eration of said start. and stopmeans by said control means, thereby maintaining said=lamps illuminatedwhen said motor generator set is stoppedby. operation of said safetymechanism.

5..In an elevator installation in which an: elevator car travels in-ahoistway and. serves several fioor landings of a building and in'whichthere are provided an elevator hoisting machine adapted for propelling.said car in said hoistway, a motor generator set for energizingsaidhoisting machine, and car position. indicating means, said: meansincluding a plurality. of electric indicating lamps, one each of whichcorresponds to a floorlanding-served by said car, said positionindicating means being' adapted to indicate visuallythe position ofsaidcar in' saidhoistway by selectively. energizing said indicatinglamps in accordance with movement of said car in said hoistway; a carposition indicator control comprising, first control means for startingand stopping said motor generator set, said first control means beingoperable from a first condition to a second condition to start saidmotor generator set running and fromsaid second'condition' to said firstcondition to stop said-motor generator set: from running, second controlmeans op.- eratively, responsive to demand for elevator. service foractuating said first control means from. said first condition.tosaidsecond condition for putting said elevator car. in serviceand from saidsecond condition to said. first condition for. taking saidelevatorcarout-of service, motor generator set. overload mechanismoperatively responsive to. an; overload of. said motor generator set,said overload mechanism being operative to actuate. said first control.means. from said second condition to said first condition when anoverload occurs to; stop said motor. generator setfromrunning, and-thirdcontrol=means for. lighting and extinguishing said. indicating. lamps,said. third control means being operatively responsive onlyto actuation.of said first control means by said second control'means.

6. In an elevator installation in which anelevator ear travels in ahoistway and serves several floor landings of a building and in whichthere are provided an elevator. hoisting machine adapted forpropellingsaid car. in .saidrhoistway, a motor: generator set. for energizingsaid. hoisting machine, and car position indicating. means, saidmeansincluding a plurality of electric indicating lamps, one each ofWhich.- corresponds; to a floor landing served by said car, saidpositionindicating, means being adapted to indicate visually the position of.said car in said; hoistway by selectively energizing said indicatinglampsin: accordance with'movement of said.- car in said hoistway; a carposition. indicator control comprising, first; control. means forstarting and stopping said motor generator set, said first controlmeans: beingv operative from afirst condition-to a second-condition tostart said motes-generator set running and from said secondcondition;to. said firstcondition to; stop said motor generatorsetrfrom' running, second control means operatively responsive to'demand for, elevator service for actuating saidfirstcontrolmeansfromsaidfirst condition to said secondcondition for putting said elevatorcar in service and. from said second condition to said first conditionfor; taking said elevator. car out of service, motorgenerator-setoverload mechanism operatively responsive to an overload ofsaid motor generator. set, said overload mechanism. being operative toactuate said first control means from said. second condition to saidfirstcondition when an overload occurs to stop said motor generator setfrom running, and third control means for extinguishing. said.indicating lamps when said motor generatorrset is taken outof operationby. actuation of said; first control: means from said second conditionto said first condition by said second control means, and formaintaining said indicating lamps illuminated when said. first controlmeans is actuated from said first con: dition to said second conditionby said overload mechanism, saidthird control means being operativelyresponsive to actuation of said first control means from saidsecondcondition to, said first condition only by said secondcontrolmeans.

No references cited.

